Core Duo Power Bug - More info

[wynand32]

In case anyone hasn't seen this, here's a very good article on the alleged Core Duo power bug. It appears that it's not specific to the Core Duo (the Sonoma Pentium M, at least, has it as well), and there's a fix that works some of the time (but, alas, not all).

http://www.anandtech.com/mobile/showdoc.aspx?i=2693

Someone on another forum mentioned that his 8204 came with the fix already implemented. I'm curious to see if anyone else has (mine is at home at the moment). I was running on battery last night, and mine lasted about 3 hours; I was hoping for closer to four with a fix implemented.

Perhaps everyone could check and report if their 8204 has the registry hack already in place... It's buried in the article somewhere, and unfortunately I don't have the few minutes I'd need to cut/paste it here...

[asspenny]

very good article

I will have to try the regfix later tonight.

Thanks!

[CoolHotCold]

For those too lazy to read the artical
SYMPTOMS

Consider the following scenario. You install Microsoft Windows XP Service Pack 2 (SP2) on a portable computer. Then, you connect a USB 2.0 device to the computer. In this scenario, the computer uses its battery power more quickly than you expect.

CAUSE

Windows XP SP2 installs a USB 2.0 driver that initializes any connected USB device. However, the USB 2.0 driver leaves the asynchronous scheduler component continuously running. This problem causes continuous instances of memory access that prevent the computer from entering the deeper Advanced Configuration and Power Interface (ACPI) processor idle sleep states. These processor idle sleep states are also known as C states. For example, these include the C3 and C4 states. These sleep states are designed, in part, to save battery power. If an otherwise idle portable computer cannot enter or maintain the processor idle sleep states, the computer uses its battery power more quickly than you expect.

RESOLUTION

Warning: Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk. To resolve this problem, add the EnIdleEndpointSupport entry to the USB registry key. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate, and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\USB

Note: If the USB subkey does not exist, create it. To do this, follow these steps:
a. Select the Services key. On the Edit menu, point to New, and then click Key.
b. Type USB in the New Key #1 box to name the new key "USB."

3. Right-click USB, point to New, and then click DWORD Value.
4. In the New Value #1 box that appears, type EnIdleEndpointSupport, and then press ENTER.
5. Right-click EnIdleEndpointSupport, and then click Modify.
6. In the Value data box, type 1, leave the Hexadecimal option selected, and then click OK.
7. Quit Registry Editor.

[CoolHotCold]

Yep my 8204 comes with the fix already there.

[wynand32]

Hmmm.... Interesting. I remembered after writing my original post that I actually put the system into sleep before noticing that it was lasting about 3 hours. Once the system goes to sleep, it must be rebooted for the fix to work again, so I'll try again tonight...

[wynand32]

Alrighty, I've checked and I have the setting as well. Currently, without letting the system go sleep, I'm projecting roughly 4 hours of battery life with the GPU set for low power and about 3.5 hours with the GPU set on "balanced."

I can live with either... If a better fix comes out to improve that, I'll be happier still, but so far I'm pleased.

[PorschePRH]

I have a new 5670 and it has that registry entry exactly as above...